1. Field Of The Invention
The invention relates to a fluid supply system in .which fluid is conducted through a recessed casing and a cover.
2. Summary Of The Prior Art
In fluid supply systems of this type, the sealing of the ducts at the junction between the casing and the cover is generally effected by means of seals. When a seal is defective, fluid leaks and proceeds to fill the recess or recesses of the casing, exerting a pressure which may deform the casing and the cover. There is a danger that this deformation could worsen the leak, or bring about further leaks from other ducts. The pressure in the recess may even detach the cover from the casing. This is particularly a problem in aeronautics where mass gains are sought through the use of thinner structures, which are easily deformable. A solution lies in establishing a communication between the recess or recesses of the casing and the outside by means of a vent, which may be a simple hole. The fluid from a leak flows out through this vent, and no longer causes a harmful pressure build-up in the recess.
One of the drawbacks of this solution is the danger of the leak being unnoticed. This is the case, for example, with an apparatus which cannot be observed directly during its operation, such as the hydraulic equipment on an aircraft. Moreover, when the fluid is a volatile substance such as fuel, the leak leaves no immediately visible traces when the apparatus has stopped.
U.S. Pat. No. 4,874,007 describes a hydraulic system including a monitoring device for detecting a perforation of an internal wall of the system. This device comprises a piston situated in a cylinder behind the wall to be monitored, the piston being integral with a visual indicator. When the wall is perforated, the pressurized fluid passes through the wall and creates a pressure in the cylinder which pushes back the piston. However, this solution cannot be used in the present situation, as the leaking fluid must be able to flow without any pressure being created in the recess or recesses of the casing.